Screen tensioning and clamping means



June 1, 1965 w. HN 3,186,547

SCREEN TENSIONING AND CLAMPING MEANS Filed Oct. 29, 1962 INVENTOR.

HTTORNEYS GEORGE W. BEHNKE v United States Patent 3,186,547 SCREEN TENSIONING AND CLAMPING MEANS George W. Behnke, Durand, Mich, assignor to Simplicity Engineering Company, Durand, Mich., a corporation of Michigan Filed Oct. 29, 1962, Ser. No. 233,722 2 Claims. (Cl. 259-403) This invention relates to machinery for screening fragmentary materials of all kinds of either wet or dry classification, and more particularly to means for connecting and securing the screen under tension to the framework of the machine.

One of the prime objects of the invention is to provide a simple, practical and economical means for securing the screen, under tension, to the framework to the end that the best screening result can be obtained.

Another object of the invention is to design a screen securing means which can be readily mounted in position, which is easily removable when desired, and which automatically maintains the screen under tension when in operation and is not loosened by vibration of the screen body.

Screening equipment of the nature herein referred to is adaptable to machines having an eccentric gyrating action, as well as so-called vibrating machines provided with an eccentric out-of-balance action. This equipment is designed for high production and normally processes thousands of tons of material within a limited period of time, and inasmuch as the material processed is usually of a high abrasive nature, the screen wears quite rapidly and requires frequent replacement. This replacement is normally a time consuming operation, requires removal of a multiplicity of nuts and bolts, and is further complicated by limited access, working space and frozen nuts. It is, therefore, important that this removal of worn screens and replacement thereof, when necessary, be simple and easily accomplished in a limited length of time to minimize both down-time and labor.

Still a further object is to design a take-up bolt and straddle type take-up wedge which automatically clamps the screen under tension on the machine deck, and which can be quickly and easily mounted and demounted using only a conventional hammer.

With the above and other objects in view, the present invention consists in the combination and arrangement of parts, hereinafter more fully described, illustrated in the accompanying drawing, and more particularly pointed out in the appended claims; it being understood that changes may be made in the form, size, proportion and minor details of construction, without departing from the spirit, or sacrificing any of the advantages of the invention.

In the drawing:

7 FIG. 1 is a sectional, end elevational view of a vibratory screen showing our take-up bolt and take-up wedge in position thereon.

FIG. 2 is an enlarged, fragmentary, front sectional view showing the machine side plate, take-up rail and bracket, machine deck with the screen, take-up bolt and wedge in position.

FIG. 3 is an end elevational view of the take-up bracket, take-up bolt and wedge.

FIG. 4 is a sectional plan taken on the line 4-4 of FIG. 2.

FIG. 5 is a transverse sectional view taken on line 5-5 of FIG. 2.

Referring now more particularly to the drawing in which I have illustrated a preferred embodiment of the invention; a screening machine is shown which includes transversely spaced, side plates 8-8, having angularly shaped support members 9 secured to the inner face there- 3,186,547 Patented June 1, 1965 "ice of to form the machine screen deck. The side plates 88 are connected by a bottom wall 8a and are resilient ly supported by conventional means (not shown) from the base rails R. A vibratory mechanism V, which may comprise an eccentric shaft S journaled by bearings a and connected to vibrate the machine deck, can be driven from a conventional electric motor (not shown) by belts b. Side take-up rails 10 are provided on the machine side plates above the members 9 and are formed as clearly shown in FIGURE 2 of the drawing, with oblong bolt openings 11 therein, the lower ends of rails 10 being inwardly turned as at 12 to lie substantially parallel with the face or surface of the screen deck to which the screen cloth C is clamped.

An elongated opening 13 is provided in each side plate 9 in the position shown, and a take-up bracket 14 is welded to the outer face of each side plate 8, the outer wall 14a of said plate being disposed at a downwardly inclined angle (see FIG. 2), and having a bolt passing opening 15 therein.

A take-up bolt B extends through each set of openings 11, 13 and 15 and is formed with an enlarged head 16 and a squared section 16a which seats in the opening 11 provided in the take-up rail and prevents rotation of the bolt B therein. The body of the bolt is generally rectangular in cross section as at 17, the free end section being formed with integral, laterally projecting, opposed shoulders or wings 18 for a purpose to be presently described.

Each take-up bracket 14 is welded to the machine side plate 8 at 19, the take-up bolt B passing therethrough and projects a predetermined distance beyond the outer face thereof to accommodate a straddling wedge W which can be driven down between the face of the take-up bracket 14 and the shoulders 18 of the take-up bolt.

The straddling wedge W is formed as clearly shown in FIGS. 2 and 3 of the drawing, and comprises spaced apart, downwardly tapered, curved legs 2020, the upper end sections 21-21 of which are bent toward each other and iiisposed and secured in facial contact by welding or the It will be observed that the lower ends of the legs 2020 are formed with inwardly pressed spots 22 to prevent inadvertent displacement of the wedge, and in practice, the end of the legs are sprung over the body of the bolt, between the wings and the face of the side plate take-up bracket, these legs being downwardly curved and are tapered so that vibration of the machine tends only to more firmly anchor the screen on the machine deck.

The side edges of the screen are usually covered with a thin, ductile edging, and are upwardly bent as at 23 so that when the wedges W are inserted between the shouldered wings 18 of the bolts and the outer face of the take-up brackets and driven down into position, the turned up edges 23 of the take-up rails tend to tension the screen edges and clamp the screen tightly in position on the deck.

Since the material being screened is usually abrasive in character, the screens must be frequently changed. This can be easily accomplished by driving the wedges W upwardly to remove them, pulling the bolts B inwardly to remove the squared sections 16a from openings 11, and then rotating the bolts f-orty five degrees so that the shoulders 18 can pass through the openings 15, 13 and 11. When a new screen S is substituted, the bolts B are replaced in like manner.

From the foregoing description, it will be obvious that I have perfected a very simple, practical and economical means for tensioning and clamping screens and screening equipment, which is particularly designed so that the screens can be quickly and easily removed and replaced when worn.

What I claim is:

1.'In a vibrated machine for screening materials including spaced apart side plates; take-up rails mounted on the inner face of each plate and having openings therein; take-up brackets secured to the outer face of each side plate; having openings therein; .a machine deck supported by said side plates; a screen supported on said machine deck and engageabie by said take-up rails; a takeup bolt formed with a flatted surface for at least one take-up rail and having a head of greater size than the opening in said rail, the bolt body passing through the opening in the take-up rail, side plate and take-up bracket;

said bolt body having'integral shoulder means at the end 7 remote from the head, and a straddle, wedge-type member formed with downwardly, tapering spaced apart legs straddling the flatted body of the bolt and interposed be tween said shoulder means and said take-up bracketfor securing one edge of the screen firmly in position on said machine deck, the openings in the said take-up bracket, side plate, and take-up rail being of a size sufiicient to pass said shoulder means.

2. In a vibrated machine for screening materials including spaced apart side plates; take-up rails mounted on the inner face of each plate and having openings therein; angularly disposed take-up brackets secured to the outer face of each side plate; and provided with an opening therethrough; a machine deck supported by said side plates; a screen supported on said machine deck and engagcable by said take-up rails; a take-up bolt formedv with a square portion provided adjacent the head of thea 4, v bolt seating in the opening through said take-up rail to prevent rotation thereof, the body of said bolt being flatted and the flatted surfaces beingaangularly disposed from theflat surfaces of said square portion, said bolt having a head of greater size than the opening in said take-up rail,

said bolt body passing through the openings in the take-up rail, side plateand take-up bracket, and having integral shoulder means at the end remote from the head; and a straddle, wedge-type member formed with downwardly, tapering, spaced apart legs straddling the body of the bolt and interposed between said shoulder means and the side plate for securing one edge. of the screen firmly in position on said machine deck, the openings in the said takeup rail and side plate being of a size suficient to pass said shoulder means.

References Cited by theExaminer UNITED STATES PATENTS HARRY, B. THORNTON, Primary Examiner.

HERBERT L. MARTIN, Examiner. 

1. IN A VIBRATED MACHINE FOR SCREENING MATERIAL INCLUDING SPACED APART SIDE PLATES; TAKE-UP RAILS MOUNTED ON THE INNER FACE OF EACH PLATE AND HAVING OPENINGS THEREIN; TAKE-UP BRACKETS SECURED TO THE OUTER FACE OF EACH SIDE PLATE; HAVING OPENINGS THEREIN; A MACHINE DECK SUPPORTED BY SAID SIDE PLATES; A SCREEN SUPPORTED ON SAID MACHINE DECK AND ENGAGEABLE BY SAID TAKE-UP RAILS; A TAKEUP BOLT FORMED WITH A FLATTED SURFACE FOR AT LEAST ONE TAKE-UP RAIL AND HAVING A HEAD OF GREATER SIZE THAN THE OPENING IN SAID RAIL, THE BOLT BODY PASSING THROUGH THE OPENING IN THE TAKE-UP RAIL, SIDE PLATE AND TAKE-UP BRACKET; SAID BOLT BODY HAVING INTEGRAL SHOULDER MEANS AT THE END REMOTE FROM THE HEAD, AND A STRADDLE, WEDGE-TYPE MEMBER FORMED WITH DOWNWARDLY, TAPERINGG SPACED APART LEGS STRADDLING THE FLATTED BODY OF THE BOLT AND INTERPOSED BETWEEN SAID SHOULDER MEANS AND SAID TAKE-UP BRACKET FOR SECURING ONE EDGE OF THE SCREEN FIRMLY IN POSITION ON SAID MACHINE DECK, THE OPENINGS IN THE SAID TAKE-UP BRACKET, SIDE PLATE, AND TAKE-UP RAIL BEING OF A SIZE SUFFICIENT TO PASS SAID SHOULDER MEANS. 